Organocatalytic Dynamic Kinetic Resolution

Description

In a classical kinetic resolution, two enantiomers of a racemate are transformed into chiral products at different rates with a maximum theoretical yield of 50%. However, the need to reduce costs and waste in synthesis have led to efforts to develop novel resolution procedures proceeding beyond this 50% limited yield. This has led to the evolution of classical kinetic resolution into dynamic kinetic resolution (DKR), allowing a quantitative yield of one of the enantiomers. DKR combines the resolution step of kinetic resolution with an in-situ racemization of the chirally-labile substrate. It is only in the last two decades that chiral green organocatalysts have been demonstrated to be capable of promoting DKRs considerably expanding the synthetic scope of the powerful concept of DKR. Collecting all the developments in the field of DKR, this book shows that a wide variety of organocatalysts allow excellent levels of stereocontrol and yields in many types of transformations. It is a great resource for academics and industrialists interested in green enantioselective catalytic reactions. Cover Contents Abbreviations Chapter 1 Introduction References Chapter 2 Dynamic Kinetic Resolutions Promoted by Cinchona Alkaloid Catalysts 2.1 Introduction 2.2 Alcoholytic/Thiolytic Ring-opening Reactions 2.2.1 Ring-opening Reactions with Alcohols 2.2.2 Ring-opening Reactions with Thiols 2.3 Domino Reactions 2.4 Nucleophilic Additions to Carbonyl Compounds 2.4.1 Cyanations 2.4.2 (Nitro)-Aldol Reactions 2.5 O-Alkylations 2.6 Brominations 2.7 Synthesis of Sulfinates 2.8 Synthesis of Phosphates/Phosphoramidates 2.9 Other Reactions 2.10 Conclusion References Chapter 3 Dynamic Kinetic Resolutions Promoted by Amino Acid Catalysts and Derivatives 3.1 Introduction 3.2 Aldol Reactions 3.3 Domino/Tandem Reactions 3.4 Reductions 3.5 Other Reactions 3.6 Conclusion References Chapter 4 Dynamic Kinetic Resolutions Promoted by Phosphoric Acid Catalysts 4.1 Introduction 4.2 Domino Reactions 4.3 Transfer Hydrogenations 4.4 Alcoholytic Ring-opening Reactions 4.5 Coupling Reactions 4.6 Other Reactions 4.7 Conclusion References Chapter 5 Dynamic Kinetic Resolutions Promoted by N-Heterocyclic Carbene Catalysts 5.1 Introduction 5.2 Benzoin Condensations 5.3 Domino Reactions 5.4 Transesterifications 5.5 Conclusion References Chapter 6 Dynamic Kinetic Resolutions Promoted by Thiourea Catalysts 6.1 Introduction 6.2 Alcoholytic Ring-opening Reactions 6.3 Domino Reactions 6.4 Acetalisations 6.5 Conclusion References Chapter 7 Dynamic Kinetic Resolutions Promoted by Pyridine-based Lewis Base Catalysts 7.1 Introduction 7.2 Domino Reactions 7.3 Other Reactions 7.4 Conclusion References Chapter 8 Dynamic Kinetic Resolutions Promoted by Tetramisole Catalysts 8.1 Introduction 8.2 Esterifications 8.3 Alcoholytic Ring-opening Reactions 8.4 Conclusion References Chapter 9 Dynamic Kinetic Resolutions Promoted by Other Organocatalysts 9.1 Introduction 9.2 α-Hydroxy Acid Catalysts 9.3 Bisguanidinium Salt Catalysts 9.4 Other Organocatalysts 9.5 Conclusion References Chapter 10 General Conclusion Subject Index